Coulomb excitation of 174Hf K-isomer. γ-ray spectroscopy with high-spin isomer beam

Abstract A new experimental technique utilizing a high-spin isomer beam (HSIB) has been developed. The HSIB of 174 Hf was produced by the 9 Be( 170 Er, 5 n ) 174 Hf reaction in inverse kinematics. By using the HSIB, the Coulomb excitation of the K π = 8 − isomer in 174 Hf was measured. The γ-rays from the 9 − level, which is the first excited state built on the isomer, were observed as well as the cascade γ-rays of the ground-state rotational band. From the measured γ-ray yield, a value of 2 ± 1 e 2 b 2 was extracted for the B ( E 2: 8 − → 9 − ). This is the first experiment of γ-ray spectroscopy by means of the HSIB-induced secondary reactions.